Authorities in NSW are prepared for COVID-19 cases to double within weeks thanks to a new strain of Omicron.
Health Minister Brad Hazzard appeared at a budget estimates hearing on Thursday as the state recorded 16,288 new cases, an increase of more than 3000 on the previous day.
"Preliminary information indicates that ... in only another month to six weeks we could be looking at cases more than double than we are currently getting," he said.
"It is concerning us greatly, that we are seeing an increase in daily cases."
Data from the University of NSW suggests Omicron's BA2 sub-variant is more transmissible.
Mr Hazzard is also concerned people have become complacent about getting a booster shot, with just 56.3 per cent of people having had three vaccine doses.
"While the community may have gone to sleep on the virus, the virus has not gone to sleep on the community," he said.
"The virus can still wreak havoc if we don't go out there and go and get our boosters fast."
The BA.2 subvariant evolved from the Omicron lineage of the virus, which was itself an offshoot of the original ancestral strain that emerged in Wuhan.
Since January, BA.2 has rapidly displaced its sister - the original Omicron - and swept to dominance in many quarters of the world, including Denmark, the Philippines, India, Singapore, Austria and South Africa - andin Australia.
According to the most recent WHO data, the subvariant has been identified through genomic sequencing in at least 74 countries.
Is it more transmissible?
Yes. The subvariant is at least 1.5 times more contagious than the original Omicron.
Bearing in mind Omicron had a four per cent growth advantage of Delta, which itself was three times as transmissible as the Wuhan strain, BA.2 is on any view the fittest variant of COVID-19 yet.
Meanwhile, there are concerns about health resources in the flood-ravaged communities in northern NSW.
One of the six evacuation centres in northern NSW could be converted into a COVID-19 isolation facility to deal with cases there.
Evacuated flood victims in northern NSW who have tested positive are being housed at Casino District Hospital, the hearing was told.
NSW Health's acting Deputy Secretary for Patient Experience and State Health Services Disaster Response Wayne Jones said the government is considering turning the evacuation centre at Goonellabah Sports and Aquatic Centre into a specific COVID-19 isolation centre for flood victims.
Mr Hazzard said the government was trying to ensure virus-positive people arriving at evacuation centres will be cared for in a safe location.
Dr Gale said cases have been reported at evacuation centres, but there have not been outbreaks.
- with Australian Associated Press
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